The primary objectives of the initial phase of this investigation were to (a) identify and evaluate various abrasion-erosion-resistant materials for repairing and improving the durability of concrete stilling basin slabs, (b) develop optimum techniques for repair and rehabilitation of stilling basins, and (c) develop guidance for designing stilling basin exit configurations to avoid entrapping abrasive materials within the basin. A survey of Corps Divisions and District offices identified 52 structures that have experienced concrete damage due to erosion. Depths of erosion ranged from a few inches to approximately 10 ft. In general, this erosion damage resulted from the abrasive effects of waterborne rocks and other debris being circulated over the concrete surface during construction and operation of the structure. A variety of materials including armored concrete, conventional concrete, epoxy resins, fiber- reinforced concrete, and polymer-impregnated concrete were used with varying degrees of success in the 31 repairs reported. The degree of success generally was inversely proportional to the degree of exposure to those conditions conducive to erosion damage. These materials have been used with various construction procedures, including dewatering and underwater repairs.